Fast Protein Liquid Chromatography (FPLC) is a form of liquid chromatography that is widely used, both in academia and industry, to separate and/or purify large quantities of various biomolecules such as proteins and DNA from complex mixtures. In FPLC a mixture containing soluble components, including the biomolecule of interest, is separated by passing it through a stationary phase with the aid of a liquid flow and the single components of the mixture are separated thereby. Depending on the elution method used, the components contained in the mixture migrate with different velocities through the stationary phase or are retained by the specific ligand interaction with the stationary phase thereby being separated from each other.
Due to its simple design, systems were developed automating FPLC. Automated FPLC based systems are inter alia manufactured by GE Healthcare, Chalfont St. Giles, United Kingdom, and marketed under the ÄKTA™ brand name.
Although simplifying the purification of biomolecules, purification cycles can only be set up to run on the current FPLC based systems where the produced flow-through or eluate containing the biomolecule of interest can be collected within a short time once it has left the system. Where the produced flow-through or eluate is not collected promptly, and thus, allowed to be exposed for a longer period, the risk of spoilage increases. Once there is spoilage in the flow-through or eluate the contained biomolecule is of no use and has to be disposed or alternatively extensively decontaminated which is time-consuming and costly. Thus, spoilage of the flow-through or eluate has to be avoided. Avoiding spoilage of the flow-through or eluate currently requires the attendance of operating personal at the time where the flow-through or eluate leaves the system, which increases, in particular for long-running cycles the amount of additional man hours for no increase in productivity. As a consequence, the running of purification cycles is set such that the time where the flow-through or eluate leaves the system falls within the regular working hours of the operating personal, which in turn restricts the timing and the number of purification cycles to be run.